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Hi,</div>
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I've been trying the new multipath configuration options in RHEL8 beta, the options are listed in <a href="https://access.redhat.com/documentation/en-us/red_hat_enterprise_linux/8-beta/html-single/8.0_beta_release_notes/index#file_systems_and_storage_2" id="LPNoLP154452">https://access.redhat.com/documentation/en-us/red_hat_enterprise_linux/8-beta/html-single/8.0_beta_release_notes/index#file_systems_and_storage_2</a>.</div>
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Below is my multipath configuration:</div>
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<span>defaults {<br>
</span>
<div> user_friendly_names yes<br>
</div>
<div> find_multipaths yes<br>
</div>
<div> marginal_path_double_failed_time 120<br>
</div>
<div> marginal_path_err_sample_time 121<br>
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<div> marginal_path_err_rate_threshold 10<br>
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<div> marginal_path_err_recheck_gap_time 30<br>
</div>
<span>}</span><br>
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and this is the multipath storage:</div>
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<span>3600124f0f822cba90003551f67355d000d dm-2 SUN,ZFS Storage 7120<br>
</span>
<div>size=100G features='1 queue_if_no_path' hwhandler='1 alua' wp=rw<br>
</div>
<div>`-+- policy='service-time 0' prio=50 status=active<br>
</div>
<div> |- 6:0:0:4 sdf 8:80 failed faulty running<br>
</div>
<div> |- 6:0:1:4 sdbv 68:144 failed faulty running<br>
</div>
<div> |- 8:0:0:4 sdab 65:176 active ready running<br>
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<span> `- 8:0:1:4 sdcy 70:96 active ready running</span><br>
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To do the test, I use dd to write to the storage and use "iostat 1" to check IO, then log onto the fc switch to disable a port, after port being disabled, two paths will fail, and IO is only seen on the remaining two paths, then I immediately re-enable the
port, and IO will again be seen on all 4 paths, and then I do this path disable and re-enable all over again, but no matter how fast I do this again and again, after re-enabling the fc switch port, the failed paths will always go online again after port re-enable
and IO are seen on them. According to the manpage of multipath.conf: "when a path failed event occurs <span>twice in marginal_path_double_failed_time seconds due to an IO</span><span> error and all the other three parameters are set, multipathd <span>will
fail the path and enqueue this path </span></span>into a queue.<span><span>..". Did I get anything wrong?</span></span></div>
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<span><span>Thanks!</span></span></div>
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<span><span>Regards,</span></span></div>
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<span><span>Khitai</span></span></div>
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